A conducting square loop of side $l$ and resistance $R$ is moving with a constant velocity $v$ perpendicular to one of its sides and entering a uniform magnetic field $B$ perpendicular to the plane of the loop. What is the magnitude of the induced current in the loop as a function of time $t$, where $t=0$ is the instant when the loop starts entering the field?

For a coil having L = 2 mH, current flows at the rate of ${10^3}\;{\rm{A}}{{\rm{s}}^{ - 1}}$. The emf induced is

Two parallel rails of a railway track insulated from each other and with the ground are connected to a millivoltmeter. The distance between the rails is one metre. A train is travelling with a velocity of $72\,\,km{{\rm{h}}^{ - 1}}$ along the track. The reading of the millivotmeter (in ${\rm{mV}}$) is : (Vertical component of the earth’s magnetic induction is $2\,\, imes {10^{ - 5}}\,{\rm{T}})$

The length of a potentiometer wire is 1 m and its resistance is $4\,\Omega$. A current of $5\,mA$ is flowing in it. An unknown source of emf is balanced on $40{\mkern 1mu} \,cm$ length of this wire, then find the emf of the source.

A circular coil with 500 turns and a radius of 0.05 m rotates at 20 rad/s in a uniform magnetic field of $10^{-2}$ T perpendicular to the axis of rotation. If the coil's resistance is 10 $\Omega$, the peak induced current is:

An axle of truck is ${\rm{2}}{\rm{.5 m}}$ long. If the truck is moving due north at $30\,\,m{s^{( - 1)}}$ at a place where the vertical component of the earth’s magnetic field is $90\,\,\mu T$, the potential difference between the two ends of the axle is

The magnetic induction in the region between the pole faces of an electromagnet is $0.7\,\,weber/{m^2}$. The induced e.m.f. in a straight conductor $10\,\,cm$ long, perpendicular to $B$ and moving perpendicular both to magnetic induction and its own length with a velocity $2\,\,m/\sec$ is

A circular loop of wire is placed near a powerful electromagnet. In which scenario is the least force required to move the loop?

A conducting rod of length 50 cm is moved perpendicular to a uniform magnetic field of 0.2 T with a velocity of 10 m/s. The induced emf across the rod is:

An inductor having coefficient of self induction ${\rm{40}}\,\,{\rm{mH}}$. What is the energy stored in it when a current of ${\rm{2 A}}$ is passed through it?

A circular metal plate of radius $R$ is rotating with a uniform angular velocity $\omega$ with its plane perpendicular to a uniform magnetic field $B$. Then the emf developed between the centre and the rim of the plate is